HA 2026.8 changes to combined devices

[doctorkb]

Home Assistant 2026.8 makes some significant changes to how devices are combined, etc. Figured this might affect the functionality of this integration, so wanted to give you a heads-up.

Public release notes: https://rc.home-assistant.io/blog/2026/07/22/release-20268/#a-cleaner-way-to-handle-your-devices

Developer Blog details: https://developers.home-assistant.io/blog/2026/07/21/device-registry-single-config-entry/

I have not tested 2026.8. Everything may work fine. But given some of the warnings around this integration, I figured it was worth bringing this up.

[MrAyianaLex]

I confirm.
I just installed the 2026.8, and I end up with 11453 messages in 10 minutes for 3 merger devices.
After removing the devices, more message in the logs.

Here are some examples (all messages are in this format)

2026-08-05 18:52:01.626 WARNING (MainThread) [homeassistant.helpers.entity_registry] Ignoring request to link entity from integration mqtt to device ba93b955f6d9bdd7c861daac1df1e77b: the device id refers to a composite device which was split into one device per config entry, please create a bug report at https://github.com/home-assistant/core/issues?q=is%3Aopen+is%3Aissue+label%3A%22integration%3A+mqtt%22
2026-08-05 18:52:01.626 WARNING (MainThread) [homeassistant.helpers.entity_registry] Ignoring request to link entity from integration command_line to device ba93b955f6d9bdd7c861daac1df1e77b: the device id refers to a composite device which was split into one device per config entry, please create a bug report at https://github.com/home-assistant/core/issues?q=is%3Aopen+is%3Aissue+label%3A%22integration%3A+command_line%22
2026-08-05 18:52:01.626 WARNING (MainThread) [homeassistant.helpers.entity_registry] Ignoring request to link entity from integration template to device ba93b955f6d9bdd7c861daac1df1e77b: the device id refers to a composite device which was split into one device per config entry, please create a bug report at https://github.com/home-assistant/core/issues?q=is%3Aopen+is%3Aissue+label%3A%22integration%3A+template%22

[EuleMitKeule]

To me it seems like HA has plans on incorporating something similar to the features this custom integration aims to achieve into the core at some point and are already making changes to progress towards that, or what do you guys think?

[doctorkb]

I suspect the opposite, actually. I think they’re trying to undo the idea of merged devices. You could reach out and ask about their roadmap.

[uSlackr]

This is exactly right. It's in the release notes saying they no longer merge devices. https://www.home-assistant.io/blog/2026/08/05/release-20268/#a-cleaner-way-to-handle-your-devices \\Greg

…

________________________________ From: Kris Benson ***@***.***> Sent: Wednesday, August 5, 2026 15:18 To: EuleMitKeule/device-tools ***@***.***> Cc: Subscribed ***@***.***> Subject: Re: [EuleMitKeule/device-tools] HA 2026.8 changes to combined devices (Issue #81) [https://avatars.githubusercontent.com/u/1383663?s=20&v=4]doctorkb left a comment (EuleMitKeule/device-tools#81)<#81 (comment)> I suspect the opposite, actually. I think they’re trying to undo the idea of merged devices. You could reach out and ask about their roadmap. — Reply to this email directly, view it on GitHub<#81?email_source=notifications&email_token=AGEO6Z6NSJT3CHTQWLP4T7D5IOB7DA5CNFSNUABFM5UWIORPF5TWS5BNNB2WEL2JONZXKZKDN5WW2ZLOOQXTKMJZGYZDKOBTGU22M4TFMFZW63VKON2WE43DOJUWEZLEUVSXMZLOOSWGM33PORSXEX3DNRUWG2Y#issuecomment-5196258355>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AGEO6Z4JGVJA7C2AHW3VIST5IOB7DAVCNFSNUABFKJSXA33TNF2G64TZHM3TKNJZGE4DONZVHNEXG43VMU5TKMBSGI4TSNJYG4Z2C5QC>. You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[EuleMitKeule]

This is groundwork for more flexible device handling we are building toward over the coming months, so think of it as a step along the way rather than the finished picture.

This part of the 2026.8 release notes is what I am talking about. I think devices no longer getting merged is part of whatever larger changes to devices they are planning. I haven't yet looked into their roadmap (which is now public afaik) so not sure what those changes will be.

[kimzeuner]

Edit: Dont know why but after some restarts today it suddenly came back and the devices with the entities are shown correct.

Has anyone else noticed issues with devices configured using Device Tools?
I have a few individual entities that I merged into devices using Device Tools. Since the update to 2026.8, no entities are being displayed for the created device.

Here is an example:
My device Heizung Badezimmer Kinder Roommind contains these entities

But when i go to the device there are no entities

[nyffchanium]

This is groundwork for more flexible device handling we are building toward over the coming months, so think of it as a step along the way rather than the finished picture.

This part of the 2026.8 release notes is what I am talking about. I think devices no longer getting merged is part of whatever larger changes to devices they are planning. I haven't yet looked into their roadmap (which is now public afaik) so not sure what those changes will be.

Sadly it doesn't look like they are planning to make devices mergeable again.
home-assistant/architecture#1226 (reply in thread)

[dimitri-frank]

Correct, I have the same understanding. That being said, I did read somewhere taht linking instead of merging will be possible. Don't get the difference though...
What is working for me right now in device tools is "assigning":

• Creating a new device and assigning entities is working (actually it didn't break with the update)
• Assigning entities to an existing device. It broke with the update but redoing the operation works. But I don't get the full editable device below once done, we have to go specifically in the device to check or to try to add a new entity. Minor issue I guess..

• Merge, never used that but from what I understand this shouldn't work anymore